• Lucian Paunescu Daily Sourcing & Research SRL Bucharest
  • Marius Florin Dragoescu University POLITEHNICA of Bucharest
  • Sorin Axinte University POLITEHNICA of Bucharest
  • Felicia Cosmulescu Cosfel Actual SRL Bucharest
  • Bogdan Paunescu Consitrans SA Bucharest
Keywords: glass foam, microwave heating, glass waste, silicon carbide, potassium nitrate, specific energy consumption


The manufacture of glass foams from container glass waste, silicon carbide as a foaming agent (1.75-1.9 wt.%) and an addition of 1:6 aqueous solution of KNO3 (0-1.75 wt.%) was performed at sintering temperatures between 913-952 ºC. Using the effect of the microwave power conversion into heat, the predominantly direct and partially indirect microwave heating reached high heating rates (25.2-28.8 ºC/min) and the specific energy consumption had very low values (0.70-0.83 kWh/kg), generally, below the values of industrial manufacturing processes. The characteristics of the glass foam products were excellent, the optimal sample obtained with 1.9% SiC and 1% KNO3 having an apparent density of 0.28 g/cm3, porosity of 87.3%, compressive strength of 5.1 MPa and pore size between 0.25-0.45 mm. The material is a very good thermal insulator for civil engineering.


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How to Cite
Paunescu, L., Dragoescu, M., Axinte, S., Cosmulescu, F., & Paunescu, B. (2021). CONVERSION INTO HEAT OF MICROWAVE POWER USED IN THE MANUFACTURING PROCESS OF GLASS FOAM. Nonconventional Technologies Review, 25(1). Retrieved from

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